Final answer:
When a single atom of an elemental species produces many individual spectral lines of different colors, it is because each atom has its own unique pattern of electron orbits.
Step-by-step explanation:
When a single atom of an elemental species produces many individual spectral lines of different colors, it is because each atom has its own unique pattern of electron orbits. These orbits determine the wavelengths of light that the atom can absorb or emit, resulting in a line spectrum. Each type of atom has its own set of electron orbits, so no two sets of spectral lines are exactly alike.
Elemental species' spectral lines are considered as an intrinsic property of the substance because they are determined by the atomic structure of the atom itself. Each element has its own set of electron orbits, which results in its own unique spectral lines. These lines can be used to identify the presence of specific elements in a gas or star, similar to how a signature can be used to identify a person.